diff mbox series

[net] tcp: use current time in tcp_rcv_space_adjust()

Message ID 1512587299.25033.11.camel@gmail.com
State Accepted, archived
Delegated to: David Miller
Headers show
Series [net] tcp: use current time in tcp_rcv_space_adjust() | expand

Commit Message

Eric Dumazet Dec. 6, 2017, 7:08 p.m. UTC 
From: Eric Dumazet <edumazet@google.com>

When I switched rcv_rtt_est to high resolution timestamps, I forgot
that tp->tcp_mstamp needed to be refreshed in tcp_rcv_space_adjust()

Using an old timestamp leads to autotuning lags.

Fixes: 645f4c6f2ebd ("tcp: switch rcv_rtt_est and rcvq_space to high resolution timestamps")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Wei Wang <weiwan@google.com>
Cc: Neal Cardwell <ncardwell@google.com>
Cc: Yuchung Cheng <ycheng@google.com>
---
 net/ipv4/tcp_input.c |    1 +
 1 file changed, 1 insertion(+)

Comments

Neal Cardwell Dec. 6, 2017, 7:54 p.m. UTC | #1 
On Wed, Dec 6, 2017 at 2:08 PM, Eric Dumazet <eric.dumazet@gmail.com> wrote:
> From: Eric Dumazet <edumazet@google.com>
>
> When I switched rcv_rtt_est to high resolution timestamps, I forgot
> that tp->tcp_mstamp needed to be refreshed in tcp_rcv_space_adjust()
>
> Using an old timestamp leads to autotuning lags.
>
> Fixes: 645f4c6f2ebd ("tcp: switch rcv_rtt_est and rcvq_space to high resolution timestamps")
> Signed-off-by: Eric Dumazet <edumazet@google.com>
> Cc: Wei Wang <weiwan@google.com>
> Cc: Neal Cardwell <ncardwell@google.com>
> Cc: Yuchung Cheng <ycheng@google.com>
> ---

Acked-by: Neal Cardwell <ncardwell@google.com>

neal
David Miller Dec. 6, 2017, 8:54 p.m. UTC | #2 
From: Eric Dumazet <eric.dumazet@gmail.com>
Date: Wed, 06 Dec 2017 11:08:19 -0800

> From: Eric Dumazet <edumazet@google.com>
> 
> When I switched rcv_rtt_est to high resolution timestamps, I forgot
> that tp->tcp_mstamp needed to be refreshed in tcp_rcv_space_adjust()
> 
> Using an old timestamp leads to autotuning lags.
> 
> Fixes: 645f4c6f2ebd ("tcp: switch rcv_rtt_est and rcvq_space to high resolution timestamps")
> Signed-off-by: Eric Dumazet <edumazet@google.com>

Applied and queued up for -stable, thanks Eric.
diff mbox series

Patch

diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index 734cfc8ff76edf3453921b50620be2986bfcfdb9..514c00732988b7e71f121953dabf88911b2324d6 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -579,6 +579,7 @@  void tcp_rcv_space_adjust(struct sock *sk)
 	int time;
 	int copied;
 
+	tcp_mstamp_refresh(tp);
 	time = tcp_stamp_us_delta(tp->tcp_mstamp, tp->rcvq_space.time);
 	if (time < (tp->rcv_rtt_est.rtt_us >> 3) || tp->rcv_rtt_est.rtt_us == 0)
 		return;